Apparatus for use in the cutting of plastic sheeting



March 26, 1940. c 5', H R AL 2,194,570

APPARATUS FOR USE IN THE CUTTING OF PLASTIC SHEETING Fi led Feb. 1, 1957 2 Sheets-Sheet 1 a 1 vu cwbow Cave/20 B. JcHA E/e doH/v L. Ora/ 5 March 26, 1940. c H F AL I 2,194,570

APPARATUS FOR USE) IN THE CUTTING F PLASTIC SHEE'iING Filed-Feb. 1, 1937 H 2 Sheets-SheetZ l v 75 66 84 ##5## 56 62 Z9 M 7-5 2 i: L I N u I I026 40 61 :22 1 I 56 I LL 60 H Mgfi 34 Julia 7 a I Patented Mar. 26, 1940 UNITED STATES APPARATUS FOR USE IN THE cUr'rINGoF I I PLASTIC SHEETING p v Conrad B. Schafer and John L. Drake, Toledo, Ohio, assignors to Libbey-Owens-Ford Glass Company, Toledo, Ohio, a corporation of Ohio Application February'l, 1937, SerialNo. 123,403

, 9.Claims. (01. 18-1) The present invention relates broadly to the handling and treatment of plastic sheeting and more particularly to the cutting and flattening of sheet plastic which is used in the making of laminated safety glass.

In the manufacture of laminated safety glass comprising two sheets of glass and a sheet of transparent plastic material interposed therebetween and bonded thereto to provide a-composite structure, the glass and plastic sheets are first cut to the desired size before being assembled and bonded together. The plastic sheeting is ordinarily received by the safety glass manufacturer in relatively large rolls upon which it l t 3' is wound in the form of a continuous ribbon.

The plastic is unwound from the roll as needed and sheets or sections of the desired shape and size cut therefrom. The cuttingis'us'ually accomplished byfirst scoring the plastic with a no suitable scriber such as, for example, a sharp needle, after which the cut section or sheetis broken out by flexing the plastic. The scoring and breaking operations are performed manually and in scoring the plastic the operator usually employs a template or pattern of the desired contour which serves as a guide for the scriber.

The plastic, uponbeing unwound from the roll,

does not ordinarily lie fiat but has-a tendency to bow or buckle as a result of its beingwound' on a} the roll and this tendency toward buckling not only renders the rapid and accurate cutting of the plastic more difficult but is also objectionable when handling the plastic and assembling it with the glass sheets. In addition to the set taken by the plastic upon the roll, the plastic. as received by the safety glass manufacturer is not always smooth but in some cases may be sli glritly wrinkled. I l

An important object of this invention is the "o provision of apparatus for facilitating the rapid,

accurate. scoring of the plastic sheeting and wherein the said sheeting is slowly but continuously withdrawn from the roll and the scoring thereof by the operator accomplished as it is 5 moving forwardly.

the pro'vision of apparatus of this character embodying means for effecting the flattening and smoothing of the plastic sheeting, preferably 5 (after the scoring thereof, whereby to remove all -wrinkles therefrom as well as eliminating all tendency of the plastic to resume the bowed or set" condition which resulted from its being wound upon the roll.

Other objects and advantages of the invention 5 will become more apparent during the course of the following description when taken in connection with the accompanying drawings.

In the drawings wherein like numerals are employed to designate like parts throughout the 10 same;

Fig- 1 is a plan view of apparatus constructed in accordance'with the invention, Fig. 2 is a longitudinal sectional View taken substantially on line 22 of Fig. 1, and

Fig. 3 is a side elevation of the plastic drawing and flattening means, partially broken away.

In the embodiment of the invention illustrated I in thedrawings, l0 designates the flat horizontal top of a stationary table orlike support over and in contact with which the plastic sheeting II, is drawn and upon which the said sheeting is adapted tobecut. The plastic sheeting is ordinarily received by the safety glass manufacturer in a relatively large roll and this roll is positioned at one end of the table III as indicated at I 2, theplastic'being withdrawn slowly but contin-f uously from said roll and over'said table by the two pairs of drawing rolls l3, l4 and I 5, marranged transversely of the table at the opposite end thereof. The supply of plastic sheeting may be supported in any desired manner but, as here shown, the roll l2 is carried by a drum 6 mounted upon a shaft 1 rotatably supported at its oppoa site ends in the supporting standards 8 and 9. 5- Durlng the travel of the plastic over the table,

. sheets or sections of the desired shape and size are adapted to be cut therefrom by one or more operators, and after the plastic passes between the rolls l3, l4 and l5, IS, the scored sheets or 40 sections may be completely broken out by simply flexing the plastic. The scoring is ordinarily achieved by placing a template or pattern of the desired contour upon the moving plastic and then drawing a scriber or the like around and in engagement with the edge of said template or pattern to effect the scoring of the plastic as indicated at I! in Fig. 1.

After the plastic has been scored but before it passes between the rolls l3, M, the upper sur- 5o face thereof may be acted upon by a suitable rotary brush it which serves to remove the small loose particles of plastic resulting from the scoring operation. l

The drawing rolls l3, l4 and l5; l6, together I so with the rotary brush [8, are carried by a supporting framework l9 mounted upon a base 20 and including the: three horizontally spaced transverse channel beams 2|, 22 and 23 upon which are supported at'opposite sides of the table the horizontal supporting plates 2d and 25. Mounted upon the supporting plates 25 and 25 and spaced thereabove are the platforms 253 and 21 to which are secured the bearing brackets 28 and 29 respectively. Extending transversely of the table and journaled in the bearing brackets 28 and 29 is a rod 30 whichpivotally carries the brush It. To this end, there is'fixed to the opposite ends of the rod 30, outwardly of bearing brackets 28 and 29, the bracket arms at and 32 provided at their outer ends with the bearing blocks 33 and 34 respectively in which is journaled the shaft 35 of brush it.

' The rotary brush i8 is maintained in yieldable engagement with the plastic'by. tension springs 36 and 31 which are attached at their upper ends to the substantially vertical lever arms 38 and 39 carried by the bracketarms 3i and 32 and at their lower ends to pins 40 and ll carried by I the platforms 26 and 27. The downward movement of the brush is limited by a stop bolt :12 positioned preferably at each end of the brush and adapted to be engaged by the respective bearing block 33 or 34. The boltdi. may be adjustably carried by a bracket 43 secured to the respective platform 26 or 21.

As shown in Fig. 3, when the brush it is lowered to engage the plastic, the lever arms 38 and 39 are inclined to the vertical in the direction of the brush so thatthe action of the springs 36 and it? tends to turn the rod 3% in a clockwise direction to urge the brush into yieldable engagement with the plastic.

it is simply necessary to swing the lever arms 38 and 39 to the left in Fig. 3 to bring the upper ends thereof at the other side of the axis of rotation of the rod 3b. This will cause the rod to be turned in a counter-clockwise direction, thereby lifting the brush from the plastic, and the springs 38 and 31 will serve to maintain the brush in elevated position until the lever arms 38 and 39 are again swung to the right to the position shown in Fig. 3.

The brush it is adapted to be positively driven from a motor 44, mounted upon the platform 26, through the interineshing gears 35 and 56 contained in the housing t? and fixed respectively to the motor shaft 58 and brush shaft The housing i7 is formed as a part of the bearing block 33 and is pivotally mounted on the motor shaft it so that the driving mechanism in no way interferes with vertical movement of brush. I i

As the plastic sheeting passes beneath the brush [8, it is supported upon a horizontal plate 49 carried by a plurality of spaced brackets 54] secured to the transverse channel beams 2| and 22. In accordance with the invention, the lower drawing rolls l3 and 65 are adapted to be pos- When it is desired to" raise the brush. out of contact with the plastic,

the horizontal supporting plate 2d and at the opposite end in bearings 5d and 55 carried by a bracket 58 mounted upon the horizontal supporting plate 25. Formed integral with or carried by the bracket 53 is a housing 5i and'mounted in this housing is a horizontal shaft 5&5 to which are keyed the worms 59 and Ed meshing with worm El and 62 fixed to the adjacent ends of rolls i3 and i5 respectively. The shaft 58 is driven from. a motor E53 through suitable reduction gearingcontained in the casing F55 and belt and pulley connections 65 and 66.

The upper rolls i i and it are pivotally carried by transverse rods 67 and 66 respectively in much the same manner that the brush bl is carried by rod 36. The rods ii? Stare rotatably mounted at one end in bearings 69 and H3 respectively carri'ed by bracket lit and at their opposite end in bearings l l and '12 respectively carried by bracket Keyed to the rod-El, inwardly of bearings and H, are the bracket arms 73 and it formed at their outer ends with hearing blocks 15 and N5 respectively in which the opposite ends of the roll i l are journaled. The roll M is also held in yieldable engagement with the plastic and t; s accomplished by tension springs i1 and it secured at their upper ends to the lever arms '59 58 fixed to the opposite'ends of the rod 61 and at their lower ends to bolts 8! carried by the brackets 53 and 55. The arrangement of the Ti and i8 and lever arms 19 and 89 is the se" is as the-arrangement of the springs and lever employed for. yieldably-urging the brush ill to engage the plastic and operate in the same manner.

The roll. it is journaled at its opposite ends in bearing blocks 82 and '83 provided at the outer ends of bracket arms M and 8% respectively dried to the rod 58 and is also yieldably held in engagement with the plastic by the tension springs 86 and 8'? fastened at their upper ends to the lever arms 88 and 88 and at their lower ends to bolts From the above, it will be seen that the rolls M and it can be raised and lowered inthe same manner as brush l8.

Either but preferably both sets of rolls l3, M and i5, :15 are adapted to be heated such as by the continuous circulation of hot water therethrough; To this end there may be arranged within each roll a longitudinally extending pipe ill provided. with a plurality of perforations in the wall thereof. The hot water is introduced into the pipe at one end of the roll through an inlet connection 92 and, after discharging through the perforations in the pipe into the interior of the roll, flows therefrom through an outlet connection 93 at the end of said roll.

When cutting plastic sheeting with the apparatus described, the roll of plastic I2 is first positioned at one end of the table it! as sh own in Fig. 1 and the free end of the plastic sheeting drawn over the table and passed successively between the rolls l3. M and 15, H3. The rotation of the rolls will serve to draw the plastic continuously over in contact with the table, with the tension or drag on the plastic being sufiicient to cause it to lie flat thereon. One or more operators at either or both sides of the table are adapted to score the plastic as itmoves forwardly and, as pointed out above, this is usually done I 5, IS, the scored'plastic is received in a receptacle 94 where the scored sheets orsections can be completely broken out by simply flexing the plastic. l

The rolls l3, l4 and l5, l6 not only serve to draw the plastic continuously over the table ID- in a manner to facilitate rapid and accurate cut ting of the plastic, but they also function as flattening rolls to iron out and smooth the plastic l5, l6 rotate at a slightly greater peripheral speed than the rolls l3, M, with the result that the length of plastic between the two pairs of rolls is maintained under tension. This tension,

coupled with the heating of the plastic by ,the rolls, selves to effectively smooth and flatten the plastic. The plastic is caused to lie flat'upon the table Hi during cutting by the drag or tension exerted thereon by the drawing rolls and is then flattened and smoothed as it passes between the- 'rolls l3, M and l5, l6.

It will thus be seen that there has been provided novel apparatus for facilitating the rapid, accurate scoring of the plastic sheeting in a substantially continuous mannerand for causing the plastic to lie flat during the scoring thereof. The apparatus provided also effects the smoothing and flattening of the plastic after scoring, thereby permitting the plastic sheets to be more easily handled and assembled with the glass sheets in the making of laminated safety glass It is of course desirable that the smallparticles of plastic resulting from the scoring operation be removed before the plastic is subjected to the heated drawing rolls and this is effected by the rotary brush |8.. i

It is to be understood that the form of the invention herewith shown and described is, to be taken as the preferred embodiment of the same, and that various changes in theshape, size and arrangement of parts may be resorted to without departing from the spirit of theinvention or the scope of the subjoined claims.

We claim:

1. In apparatus of the character described for the cutting and flattening of plastic sheeting, a substantially flat horizontal cutting table over which the plastic sheeting is adapted to be continuously drawn and upon which it is adapted to be cut during movement thereof, means for draw ing the plastic sheeting over said cutting table including two pairs of superimposed rolls between which said sheeting is successively passed, means for driving the second pair of superimposed rolls at a relatively greater peripheral speed than the first pair of rolls, and means for heating said rolls.

2. Inapparatus of the character described for the cutting and flattening of plastic sheeting, a substantially flat horizontal cutting table over which the plastic sheeting is adapted to be continuously drawn and upon which it is adapted to be cut duringmovement thereof, means for drawing the plastic sheeting over said cutting table including two horizontally spaced pairs of superimposed rolls between which said sheeting is successively passed, means for driving the second pair of rolls at a relatively greater peripheral speed than the first pair of rolls, means for heating said rolls, and a brush positioned inadvance of the rolls acting upon the upper surface of the sheeting.

3.- In apparatus of the character described substantially flat horizontal cutting table: over which the plastic sheeting is adapted tobe continuously drawn and upon which it is adapted to be cut during movement thereof, means for drawing the plastic sheeting over said cutting table including'two pairs of superimposed rolls between which said sheeting is successively passed, means for driving the second pair of superimposed rolls at arelatively greaterperipheral speed than the first pair of rolls, and means for internally heating said rolls.

4. In apparatus of the character described for.

the cutting and flattening of plastic sheeting, a substantially flat horizontal cutting table over which the plastic sheeting is adapted to be continuously drawn and upon which it is adapted to be cut during movement thereof, means for drawing the plastic sheeting over said cutting table including two horizontally spaced pairs of superimposed rolls between which said sheeting is successively passed, means for driving the second pair ofrolls at a relatively greater peripheral speed than the first pair of rolls, means for internally heating said rolls, and a rotary brush positioned in advance of the rolls acting upon the upper surface of the sheeting.

5. In apparatus of the character described for the cutting and flattening of plastic sheeting, a substantially flat horizontal cutting table over which the plastic sheeting is adapted to be continuously drawn and upon which it is adapted to be cut during movement thereof, means for drawing the plastic sheeting over said cutting table including two horizontally spaced pairs of superimposed rolls between which said sheeting is successively passed, means for positively driving the lower rolls, the upper rolls being idler rolls, and means for heating both the upper and lower rolls, means for driving the second pair of for the cutting and flattening of plastic sheeting, a

rolls at a relatively greater peripheral speed than the first pair of rolls to maintain the plastic sheeting between the twopairs of rolls under tension. v

6. In apparatus of the character described for the cutting and flattening of plastic sheeting, a substantially flat horizontal cutting table over which the plastic sheeting is adapted to be continuously drawn and upon whichv it is adapted to be cut during movement thereof, means for drawing the plastic sheeting over said cuttin table including two horizontally spaced pairs of superimposed rolls between which the sheeting issuccessively passed, means for internally heating said rolls, means for positively driving the lower rolls, means for pivotally supporting the upper rolls for vertical movement, and means for mounting said upper rolls for free rotation,

means for driving the second pair of superimposed rolls at a relatively greater peripheral speed than the first pairqof rolls to maintain the plastic sheeting between the two pairs of rolls under tension.

.7. In the cutting and flattening of plastic metallic surfaces'to the other, and in -finally;

breaking the sheeting along the scored lines.

8. In the cutting and flattening. of plastic sheeting, the method which comprises drawing the sheeting over and in contact with a fiat horizontal supporting surface, scoring the sheeting as it travels over said surface, brushing the upper surface of the sheeting subsequent to scoring," then passing the scored sheeting successively be-- tween two pairs of heated metallic surfaces, placing the sheeting under tension as it passes from one pair of heated metallic surfaces to theother, and in finally breaking the sheeting along the scored lines.

passed, and means for driving the second pair of 10 superimposed rolls at a relatively greater periph eral speed than the first pair of rolls.

CONRAD B. SCHAFER JOHN L. DRAKE. 

